Often why the discipleship process doesn’t multiply is because we leave it all up to one person. If one person disciples one other person, then that person disciples one other person… and so on. The assumption is that one person can bring another person to maturity all on their own—and that’s a fallacy.
There are several reasons why that doesn’t work, but one is that we are not Jesus. As much as we may strive to be like him, Jesus had all of the spiritual gifts; most of us just have a few. Jesus was able to develop his disciples alone because he had all the gifts. Now the gifts of the Spirit are distributed to the church as a whole; now it takes a village. Today the expression of Jesus isn’t done by an individual exclusively, but by a community of individuals. It is only collectively that we can do the work of Jesus.